Koch M
Universität Tübingen, Germany.
Behav Neurosci. 1996 Jun;110(3):468-77. doi: 10.1037//0735-7044.110.3.468.
Prepulse inhibition (PPI) of the acoustic startle response (ASR) can be used as an operational measure for brain mechanisms that prevent disruption of ongoing stimulus processing routines by other stimuli and that thereby avoid behavioral interference. Deficient PPI has been observed in schizophrenics; therefore, much interest has been devoted to the understanding of the neural basis of PPI. This study investigated the role of the septohippocampal system in the modulation of PPI in rats. Stimulation of the medial septum by injection of the glutamate agonist kainate led to a profound disturbance of PPI and reduced the ASR amplitude. The PPI deficit induced by intraseptal kainate was attenuated by systemic or intrahippocampal administration of the acetylcholine antagonist scopolamine. Lesions of the medial septum, made by the neurotoxin AMPA, did not affect PPI. The present data indicate that activation of the septohippocampal system reduces PPI of the ASR, suggesting its role in sensorimotor gating.
听觉惊跳反应（ASR）的前脉冲抑制（PPI）可作为一种操作性指标，用于衡量大脑中防止其他刺激干扰正在进行的刺激处理程序从而避免行为干扰的机制。在精神分裂症患者中观察到PPI缺陷；因此，人们对理解PPI的神经基础投入了大量关注。本研究调查了大鼠中隔海马系统在调节PPI中的作用。通过注射谷氨酸激动剂海藻酸刺激内侧隔区，导致PPI严重紊乱并降低了ASR幅度。全身性或海马内注射乙酰胆碱拮抗剂东莨菪碱可减轻内侧隔区内注射海藻酸所诱导的PPI缺陷。由神经毒素AMPA造成的内侧隔区损伤并不影响PPI。目前的数据表明，中隔海马系统的激活会降低ASR的PPI，提示其在感觉运动门控中的作用。
